1. Field of the Invention
The present invention relates to methods of manufacturing materials from recycled plastic and the materials produced thereby.
2. Related Art
Plastic includes a variety of synthetic and semi-synthetic materials. They are typically composed of organic polymers and may contain other substances to achieve desired characteristics. There are also some natural polymers generally considered to be “plastics.” Examples of plastics include High Density Polyethylene (HDPE), Low Density Polyethylene (LDPE), Polypropylene (PP), Polyethylene Terephthalate (PET), Polyvinyl Chloride (PVC), and Polystyrene (PS).
Plastics may be sorted according to their resin identification codes and recycled. Recycling methods include taking scrap or waste plastics, reprocessing them and turning them into useful products. One relevant reprocessing method that can be applied to a large family of plastic material is called heat compression. In this method, the plastic material is liquefied while spinning in a large drum. The resulting liquefied plastic is then pumped into casting molds and re-made into a new useful material. This process, however, is not energy efficient. Plastic recycling in general can be expensive due to the costs associated with running the heat compression machinery and the work required to sort and reprocessing various plastic materials. The presence of additives, dyes and fillers in plastic can also complicate the recycling of plastics. For these reasons and others, there is a need for improved systems and methods of plastic recycling.